1661433636 has 24 divisors (see below), whose sum is σ = 3881715264. Its totient is φ = 553091680.

The previous prime is 1661433629. The next prime is 1661433643. The reversal of 1661433636 is 6363341661.

It is an interprime number because it is at equal distance from previous prime (1661433629) and next prime (1661433643).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 1661433594 and 1661433603.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80280 + ... + 98831.

It is an arithmetic number, because the mean of its divisors is an integer number (161738136).

Almost surely, 2^1661433636 is an apocalyptic number.

It is an amenable number.

1661433636 is an abundant number, since it is smaller than the sum of its proper divisors (2220281628).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1661433636 is a wasteful number, since it uses less digits than its factorization.

1661433636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179891 (or 179889 counting only the distinct ones).

The product of its digits is 139968, while the sum is 39.

The square root of 1661433636 is about 40760.6873838016. The cubic root of 1661433636 is about 1184.3889117220.

The spelling of 1661433636 in words is "one billion, six hundred sixty-one million, four hundred thirty-three thousand, six hundred thirty-six".